Repeating defects – HP LaserJet Enterprise M4555 MFP series User Manual
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3.
Examine the surface of the green imaging drum on the bottom of the print cartridge.
CAUTION:
Do not touch the green roller (imaging drum) on the bottom of the cartridge.
Fingerprints on the imaging drum can cause print-quality problems.
4.
If you see any scratches, fingerprints, or other damage on the imaging drum, replace the print
cartridge.
5.
If the imaging drum does not appear to be damaged, rock the print cartridge gently several times
and reinstall it. Print a few pages to see if the problem has resolved.
Repeating defects
If defects repeat at regular intervals on the page, use a ruler to identify the cause of the defect. Place
the top of the ruler at the first defect. The marking that is beside the next occurrence of the defect
indicates which component needs to be replaced.
Distance between defects
Product components that cause the defect
37.7 mm (1.5 in)
Primary charging roller
47 mm (1.85 in)
Transfer roller
63 mm (2.5 in)
Developer roller
Tray 1 pickup roller
79 mm (3.1 in)
Tray 1 feed roller
Tray 1 separation roller
Tray 2 feed roller
Tray 2 pickup roller
Tray 2 separation roller
94 mm (3.75 in)
Fuser sleeve unit or pressure roller
Photosensitive drum
114
Chapter 7 Manage supplies
ENWW